首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 484 毫秒
1.
On June 1, 2017, President Trump announced the United States' withdrawal from the Paris agreement on climate change. Despite this decision, American firms continued investing in low-carbon technologies and some states committed to tougher environmental standards. To understand this apparent paradox, this paper studies how a weakening of environmental standards affects the behavior of profit-maximizing firms. It finds that a relaxation of emission standards (i) may increase firms’ incentives to adopt clean technologies, but not to pollute less; (ii) may negatively affect industry profitability if it is perceived as temporary; and, when this is the case, (iii) the unilateral adoption of stricter standards by large states may increase the expected profitability of every firm.  相似文献   

2.
● Established a quantification method of pollutant emission standard. ● Predicted the SO2 emission intensity of single coking enterprises in China. ● Evaluated the influence of pollutant discharge standard on prediction accuracy. ● Analyzed the SO2 emissions of Chinese provincial and municipal coking enterprises. Industrial emissions are the main source of atmospheric pollutants in China. Accurate and reasonable prediction of the emission of atmospheric pollutants from single enterprise can determine the exact source of atmospheric pollutants and control atmospheric pollution precisely. Based on China’s coking enterprises in 2020, we proposed a quantitative method for pollutant emission standards and introduced the quantification results of pollutant emission standards (QRPES) into the construction of support vector regression (SVR) and random forest regression (RFR) prediction methods for SO2 emission of coking enterprises in China. The results show that, affected by the types of coke ovens and regions, China’s current coking enterprises have implemented a total of 21 emission standards, with marked differences. After adding QRPES, it was found that the root mean squared error (RMSE) of SVR and RFR decreased from 0.055 kt/a and 0.059 kt/a to 0.045 kt/a and 0.039 kt/a, and theR2 increased from 0.890 and 0.881 to 0.926 and 0.945, respectively. This shows that the QRPES can greatly improve the prediction accuracy, and the SO2 emissions of each enterprise are highly correlated with the strictness of standards. The predicted result shows that 45% of SO2 emissions from Chinese coking enterprises are concentrated in Shanxi, Shaanxi and Hebei provinces in central China. The method created in this paper fills in the blank of forecasting method of air pollutant emission intensity of single enterprise and is of great help to the accurate control of air pollutants.  相似文献   

3.
以北京海淀区为例,对密闭式垃圾清洁站的分布及内外部的大气状况进行了监测并运用大气扩散模型探讨了垃圾清洁站的安全防护距离.结果表明:海淀区垃圾清洁站的分布不均衡;所有垃圾清洁站内外的大气污染物中,H2S、NH3、S02、N02、二硫化碳、苯乙烯、TSP、CO等指标均符合中国相关排放标准;转运站内部三甲胺、甲硫醇、甲硫醚、...  相似文献   

4.
Habitat variability makes site-specific considerations a necessity in the specification of water quality standards. The U.S. Environmental Protection Agency (EPA) has recognized this in its development of procedures for site-specific modification of national standards. These procedures involves translation of laboratory toxicology data into field situations where such data are often poor predictors of biotoxicity. The whole problem is poorly specified.This paper formulates a system theory approach to better specification of the problems associated with setting water quality standards. A state space model of the general environmental protection problem is presented: Find a set of diagnostic variables whose maintenance within specifiable limits (standards) is both necessary and sufficient to protect all variables of a subject ecosystem. The program for this comprises a site-specific protocol.Stages in such a protocol include (1) choice of diagnostic variables, (2) establishment of necessity and sufficiency for these variables, and (3) determination of standards through (4) toxicity testing. Problems associated with the latter include (a) spatiotemporal variability, system (b) linearity-nonlinearity, and (c) stationarity-nonstationarity, and (d) monitoring for: baseline information, impact detection, determining compliance, establishing causality and making predictions. Each of these problems is structured in terms of the state space model. Then, current procedures of the EPA site-specific methodology are reviewed, and a set of recommendations proposed for their improvement using the system theory formulation to guide further developments.  相似文献   

5.
We study the optimal time path for clean energy innovation policy. In a model with emission reduction through clean energy deployment, and with R&D increasing the overall productivity of clean energy, we describe optimal R&D policies jointly with emission pricing policies. We find that while emission prices can be set at the Pigouvian level independently of innovation policy, the optimal level of R&D subsidies and patent lifetime change with the stages of the climate problem. In the early stages of clean energy development, innovators find it more difficult to capture the social value of their innovations. Thus, for a given finite patent lifetime, optimal clean energy R&D subsidies are initially high, but then fall over time. Alternatively, if research subsidies are kept constant, the optimal patent lifetime should initially be long and fall over time.  相似文献   

6.
In this paper we present, for the first time, data on the combustion of Miscanthus × Giganteus straw and pellets. We found that the heating value of Miscanthus is 17.744 MJ/kg. The gaseous emission indices of SO2, NO x and total organic carbon (TOC) in the exhaust are reported and compared with the European standards for biomass boilers. On the basis of our results, it is possible to evaluate a net energy yield between 152 and 326 MJ/hectare/year for the cultivation of Miscanthus with an energy balance estimated to be in the range of 7.7–15.4. According to the presented results, it seems reasonable to consider Miscanthus as a promising candidate as alternative fuel.  相似文献   

7.
从立法和技术角度系统分析了美国水环境标准及其实施的体系。美国水环境标准体系由环境水质标准和废水排放标准构成,制定这两种标准时不是力求完美,而是着重其实用性,考虑其在职能上互为补充;同时在实施中水环境标准也不是孤立起作用,而是依赖法律制度如许可证制度、市场手段如排放权交易等,构成一个完整的水环境标准及其实施体系。这对我国环境标准的制定和实施颇有借鉴作用  相似文献   

8.
Impacts of industrial restructuring and upgrade on air quality & health are assessed. An integrated approach combining different models is used for the assessment. Industrial technology upgrading is more effective than economic restructuring. Ozone is much more difficult to mitigate than PM2.5. In this study, we have analyzed possible policy options to improve the air quality in an industrialized region—Beijing, Tianjin and Hebei (BTH) in China. A comprehensive model framework integrating GAINS-China, GEOS-Chem, and IMED/HEL is established to investigate the impacts of various policies on air pollution and health effects. The model establishes a data interface between economic input/output data and the emission inventory of atmospheric pollutants in the BTH region. Based on in-depth analyses of pollutant emission standards, industrial structure, pollution-intensive industries, and emission intensities in BTH and Pearl River Delta, several scenarios are constructed to explore the effectiveness of policy pathways in improving air quality in the BTH region. These scenarios include two categories: the category of “Industrial Technology Upgrade Policy” scenarios that focuses on reducing the emission intensity of industries vs. that of “Industrial Structure Adjustment Policy” scenarios that focuses on adjusting the proportion of industrial value-added. Our results show that the policy path of industrial technology upgrading can be effective and feasible, while economic structure adjustment shows complex and mixed effectiveness. We also find that the proposed policies and measures will be efficient to reduce pollution of primary pollutants and fine particles, but may not effectively mitigate ambient ozone pollution. Ozone pollution is projected to become increasingly severe in BTH, placing a challenge to pollution mitigation strategies that requires further adjustments to address it.  相似文献   

9.
ABSTRACT

Low-carbon development is an essential measure to combat climate change, and the establishment of low-carbon standards is an important means to achieve low-carbon development. Due to the differences in size and development level among counties of China, the applicability and fairness of county-level low-carbon standards are very important in this country. This study analyzed the trends of county-level carbon emissions in China, defined the peak value of carbon emissions per capita, summarized the characteristics of existing low-carbon standards, and proposed a fair county-level low-carbon standard based on carbon emissions per capita. The results of our analysis suggest that, under the constraints of carbon emissions reduction policies, China’s carbon emissions per capita will tend towards a stable range. Additionally, by referring to predictions results of the peak value of China’s carbon emissions per capita, it was determined that, in low-carbon development targets, China’s county-level carbon emissions per capita should be set within the range of 2–4 tons. Besides setting low-carbon standards, the Chinese government and private enterprises should develop low-carbon technologies as soon as possible and innovate management models to achieve the win–win situation of simultaneous economic growth and carbon emissions reduction.  相似文献   

10.
A number of linear programming models purport to minimize the costs of emission control to achieve ambient air quality standards. Many of the simulations incorporate the simplifying assumption that improvements in ambient air quality are proportional to reductions in regional emissions. This approach minimizes the cost of mass emission reduction, but not the cost to achieve a prescribed ambient air quality. The costs of this emissions least-cost strategy are compared to an ambient least-cost strategy which does achieve prescribed ambient air quality at minimum cost. The cost saving achieved by this strategy relative to the emissions least-cost strategy is as much as 50670. In addition, both are compared to a strategy typical of those currently used by the states, which is found to be as much as ten times as expensive as the ambient least-cost strategy.  相似文献   

11.
中国生物多样性重点保护区评价标准探讨   总被引:4,自引:0,他引:4  
从基于景观大尺度的评价和基于保护区域小尺度的评价2个层次,综述了国内外研究者在生物多样性重点区域评价方面开展的工作.尝试构建一般标准和鉴定标准的双重中国生物多样性重点保护区评价标准.其中,一般标准是作为重点保护区的基本条件,必须全部满足,而鉴定标准是依据相应指标进行判断,凡具有任意1项或多项指标的区域可被确认为重点保护区.并就指标体系和评价标准的具体内涵作了阐述.  相似文献   

12.
介绍了美国大气固定源排放标准的体系、标准内容、标准制定程序与标准实施的有关规定。并分析了其特点。  相似文献   

13.
美国露天采矿环境保护标准及其对我国的借鉴意义   总被引:1,自引:1,他引:1  
概述了美国露天采矿环境保护标准并总结其特点:(1)一般性和特殊性相结合;(2)采矿破坏地生态恢复涵义广,涉及矿区内所有受扰地区;(3)管理当局可针对具体矿山更改某些要求;(4)有完善的配套法规保障标准的执行。基于美国在采矿环境保护方面的经验,提出了我国矿产开发生态保护与恢复标准制定的4点设想:(1)涵盖矿产开发造成生态影响的每一个环节和所有的受扰地区;(2)尽量考虑各种具体情况;(3)体现生态恢复的全面性;(4)完善相关法规,保障标准实施。  相似文献   

14.
会计信息是控制和监督经济活动的主要依据和手段,是社会经济有效运行的重要基础.我国目前会计信息失真之所以成为普遍现象,其根本原因之一就是在企业制度转型期的企业产权归属关系界定不清楚,导致企业会计信息失真的受害对象不明确,因而无法实施有效的监督.因此从会计制度、会计环境、会计方法等方面进行研究,并提出了相应的对策及建议.参6.  相似文献   

15.
The deposition of untreated waste is illegal after the year 2005 on account of the new Technical Instructions for Housing Refuse (Technische Anleitung (TA) Siedlungsabfall). Therefore, the thermal treatment of waste is becoming more important than in the past. The traditionally used grate firing with steam boilers has potential for improvement. The characteristics of the different types of pyrolysis processes are explained and compared using the experience of projects planned, or already realized, in the state of Bavaria. This paper takes credit of the waste pyrolysis plant in Burgau, which is in operation since 1983, and the advanced pyrolysis plants in Fürth (Schwelbrenn-process) and in Ansbach (Thermoselect-process). The conversion-process is another newly developed method of thermal waste treatment. Some information will also be given about the pyrolysis plant for plastics in Ebenhausen. A comparison of the emission of conventional grate firing, and of 2-stage pyrolysis processes with the standards of the German laws for emission (17th BImSchV) shows, that all these processes, if planned correctly, meet the legal standards of emission. It is expected that in the future different thermal processes for waste treatment will prove successful, depending on the task.  相似文献   

16.
Recent surveys of recovery plans indicate that criteria, such as population sizes, for delisting species from the U.S. Endangered Species Act (ESA) are often unrealistically low by scientific standards. We describe the delisting criterion for the threatened southern sea otter (Enhydra lutris nereis) developed by the Southern Sea Otter Recovery Team. A major oil spill is the most serious threat to this sea otter population. After extensive modeling of oil spills, the recovery team concluded that it was not scientifically defensible to develop a delisting criterion in terms of a single probability of extinction over a specified time period. Instead, the team decided to define a size at which it would consider the population endangered and to consider the population threatened as long as a major oil spill might reduce it to that size. The effective population size (Ne) for endangered status was set at 500, estimated to be about 1850 otters. Using a spill the size of the Exxon Valdez spill (250,000 bbl), the oil spill model was iterated to generate a frequency distribution of the number of sea otters contacted by oil, from which the team estimated that less than 800 otters would be killed by 90% of the simulated spills. Thus, the delisting criterion was set at 1850 + 800 = 2650 individuals. There have been several proposals to improve the Endangered Species Act by providing quantitative guidance, in the form of specific probabilities of extinction within some time frame or specific criteria like those used by the World Conservation Union as to the levels of extinction risk represented by the terms "threatened" and "endangered." Experiences of the Sea Otter Recovery Team indicate that guidelines should not be overly rigid and should allow flexibility for dealing with specific situations. The most important consideration is to appoint a recovery team that is both technically well qualified and unconstrained by pressures from management agencies.  相似文献   

17.
This paper develops an analytical framework for comparing the welfare effects of energy efficiency standards and pricing policies for reducing gasoline, electricity, and nationwide carbon emissions. The model is parameterized with US data and includes key externalities in the energy/transportation sectors and possible underinvestment in energy efficiency due to “misperceptions” over energy savings. Even with large misperceptions, the extra welfare gains from complementing efficient pricing policies with energy efficiency standards are zero for reducing gasoline and 5 percent for reducing electricity. And when viewed as substitutes, these standards forgo 60 percent or more of the potential welfare gains from corresponding pricing policies. A combination of energy efficiency and emissions standards is more than three times as costly as carbon pricing when there is no misperception over energy savings, and even with large misperceptions, combining carbon pricing with gasoline/electricity taxes is better than combining it with energy efficiency standards.  相似文献   

18.
This paper utilizes two least-cost emission control strategies and develops rules for structuring and implementing optimal air quality standards. A strategy typical of those currently enforced, based on the State Implementation Plans (SIP's ), is compared to two least-cost strategies: (i) ambient least cost (ALC ), which achieves required air quality at least cost; and (ii) emissions least cost (ELC ), which achieves required emissions reduction at least cost. A demonstration is given of the theoretically derived result that the ALC strategy should be utilized in cost-benefit analyses to determine air quality standards and to generate emissions taxes. Preliminary analysis of the St. Louis area indicated tentative justification for a particulate ambient standard at least as strict as the current Federal primary standard. The efficiency, equity, and administrative costs for implementation of strategies based on the least-cost concept are also examined.  相似文献   

19.
介绍了热电联产的基本类型和一般规划原则,分析了热电联产规划为社会、经济及环境带来的效益,论证了热电联产是城市能源、环境协调发展的必由之路。通过SO2总量排放的分析,导出热电联产与分散供热能源利用方式所产生SO2排放总量的比较方法和计算模式。  相似文献   

20.
In the context of coastal management the aim of this paper is to present the development of a fuzzy model through the application of a Genetic algorithm in order to select the most appropriate set of variables and improve our understanding with a set of rules. The case studied is the chlorophyll response as bioindicator of ecological status in the Northeast coastal upwelling system of Rio de Janeiro state, Southeastern of Brazil. The prediction of the fuzzy model has shown an improved performance when compared to the traditional approaches as Multiple Regression modelling. The results show that the set of inferred rules can assess three different water masses. Despite the increased occurrence of upwelling is observed in spring–summer period and some instability of the model, it is able to forecast some chlorophyll peaks. We conclude that the sampling frequency is crucial to reach a better performance.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号